From 765dbb443d3c067e8a0455125ccf9f0c3f82a4c1 Mon Sep 17 00:00:00 2001
From: David Hill <dhill@conformal.com>
Date: Wed, 23 Apr 2014 18:08:57 -0400
Subject: [PATCH] Fix a bug in fetching the XML URL.

In Discover, the reponse was lowercased for comparison.  However,
this caused a 404 - Not found when fetching the url provided by
the location header if the url contained uppercase.

ok @owainga
---
 upnp.go | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/upnp.go b/upnp.go
index 269ac7ed..86a2748c 100644
--- a/upnp.go
+++ b/upnp.go
@@ -110,8 +110,7 @@ func Discover() (nat NAT, err error) {
 		// HTTP header field names are case-insensitive.
 		// http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2
 		locString := "\r\nlocation: "
-		answer = strings.ToLower(answer)
-		locIndex := strings.Index(answer, locString)
+		locIndex := strings.Index(strings.ToLower(answer), locString)
 		if locIndex < 0 {
 			continue
 		}